We describe Passpet, a tool that improves both the convenience and security of website logins through a combination of techniques. Password hashing helps users manage multiple accounts by turning a single memorized password into a different password for each account. User-assigned site labels (petnames) help users securely identify sites in the face of determined attempts at impersonation (phishing). Password-strengthening measures defend against dictionary attacks. Customizing the user interface defends against user-interface spoofing attacks. We propose new improvements to these techniques, discuss how they are integrated into a single tool, and compare Passpet to other solutions for managing passwords and preventing phishing.

The small size of handheld computers provides theconvenience of mobility at the expense of reduced screen space for display and interaction. Prior research has identified the value of spatially aware displays, in which a position-tracked display provides a window on a larger virtual workspace. This paper builds on that work by suggesting two-handed interaction techniques combining pen input with spatially aware displays. Enabling simultaneous navigation and manipulation yields the ability to create and edit objects larger than the screen and to drag and drop in 3-D. Four prototypes of the Peephole Display hardware were built, and several Peephole-augmented applications were written, including a drawing program, map viewer, and calendar. Multiple applications can be embedded into a personal information space anchored to the user's physical reference frame. A usability study with 24 participants shows that the Peephole technique can be more effective than current methods for navigating information on handheld computers.

There are currently two dominant interface types for searching and browsing large image collections: keyword-based search, and searching by overall similarity to sample images. We present an alternative based on enabling users to navigate along conceptual dimensions that describe the images. The interface makes use of hierarchical faceted metadata and dynamically generated query previews. A usability study, in which 32 art history students explored a collection of 35,000 fine arts images, compares this approach to a standard image search interface. Despite the unfamiliarity and power of the interface (attributes that often lead to rejection of new search interfaces), the study results show that 90% of the participants preferred the metadata approach overall, 97% said that it helped them learn more about the collection, 75% found it more flexible, and 72% found it easier to use than a standard baseline system. These results indicate that a category-based approach is a successful way to provide access to image collections.